1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/bpf.h> 3 #include <bpf/bpf_helpers.h> 4 #include "xdpsock.h" 5 6 /* This XDP program is only needed for the XDP_SHARED_UMEM mode. 7 * If you do not use this mode, libbpf can supply an XDP program for you. 8 */ 9 10 struct { 11 __uint(type, BPF_MAP_TYPE_XSKMAP); 12 __uint(max_entries, MAX_SOCKS); 13 __uint(key_size, sizeof(int)); 14 __uint(value_size, sizeof(int)); 15 } xsks_map SEC(".maps"); 16 17 static unsigned int rr; 18 xdp_sock_prog(struct xdp_md * ctx)19SEC("xdp_sock") int xdp_sock_prog(struct xdp_md *ctx) 20 { 21 rr = (rr + 1) & (MAX_SOCKS - 1); 22 23 return bpf_redirect_map(&xsks_map, rr, XDP_DROP); 24 } 25